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Brushing your teeth may impact more than just your oral and heart health; it may have an influence over your brain and cognitive function, according to a new study. Research out of King’s College London and the University of Southampton has found that gum disease may be associated with faster cognitive decline among people with early Alzheimer’s disease. This isn’t the first time researchers have found a potential connection between poor oral health and chronic disorders, including Alzheimer’s, but it brings up a frequently revisited question: Can oral hygiene truly have an impact on the brain and cognitive function?

The researchers examined 59 participants who had mild to moderate Alzheimer’s disease, and found that inflammatory conditions like gum disease are somehow related to cognitive decline. The team measured participants’ cognitive ability, as well as inflammatory markers in their blood samples. The participants also visited a dental hygienist, who assessed the level of their oral health. The researchers followed up with the participants six months later. Interestingly, they found that if a person had gum disease, they had a six-fold increase of cognitive decline at the six month assessment, and increased inflammation.

“These are very interesting results, which build on previous work we have done that shows that chronic inflammatory conditions have a detrimental effect on disease progression in people with Alzheimer’s disease,” said Professor Clive Holmes of the University of Southampton, senior author of the study, in the press release. “Our study was small and lasted for six months so further trials need to be carried out to develop these results. However, if there is a direct relationship between periodontitis and cognitive decline, as this current study suggests, then treatment of gum disease might be a possible treatment option for Alzheimer’s.”

It’s tough to tell whether it’s a situation of causation or correlation. It’s possible that people with worse cognitive symptoms in Alzheimer’s may be more likely to develop gum disease because of an impaired ability to take care of themselves and their oral health, Dr. Mark Ide of the Dental Institute at King’s College London said in the statement.

Although a 2013 study found gum disease bacteria in the brains of Alzheimer’s patients, scientists still remain skeptical about the link between oral hygiene and Alzheimer’s disease. It’s likely that the bacteria were able to penetrate the blood brain barrier more easily because Alzheimer’s causes inflammation in the brain, but this doesn’t mean the bacteria in any way caused Alzheimer’s. Gum disease has also been linked to breast cancer, colorectal cancer, and heart problems, though most evidence remains inconclusive.

Though these associations remain unclear, the Alzheimer’s Society encourages dementia patients to maintain good oral hygiene throughout all stages of the disease. Whether oral health can be a doorway into overall health, brushing and flossing your teeth is an important part of self-care that shouldn’t be tossed to the side.